Historical Volatility (Close-to-Close) (20-Day)
Historical Volatility (Close-to-Close): The past volatility of the security over the selected time frame, calculated using the closing price on each trading day.
Arthur J. Gallagher & Co. (AJG) had 20-Day Historical Volatility (Close-to-Close) of 0.3574 for 2026-05-21.
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